1. Field of Invention
The present invention relates to a backlight system of a Liquid Crystal Display (LCD), and more particularly to a backlight module driving system and a driving method thereof.
2. Related Art
FIG. 1 is a schematic system driving timing diagram of three-dimensional (3D) image shutter glasses of the prior art. In the prior art, a 3D image display technology includes a glasses-based technology. In a shutter-based 3D image technology, a 3D image effect is achieved mainly by increasing a high update frequency (higher than 120 Hz/screen) of a screen, which is an active 3D image technology. After a 3D image signal is provided for a display, a screen with an update frequency being 120 Hz presents a left-eye screen and a right-eye screen generated alternately in a screen sequence format. The alternation of the screens of the display should be synchronized with the operating of shutter glasses. That is to say, when the display displays the left-eye screen, the shutter glasses only enables a left-eye lens, and when the display displays the right-eye screen, the shutter glasses only enables a right-eye lens. Thus, a left eye of a viewer can only see the left-eye screen, and a right eye of a viewer can only see the right eye screen. The different screens seen by the two eyes of the viewer cause an illusion in the brain of the viewer due to a vision persistence effect of human eyes, and therefore the viewer can see a 3D image.
As shown in FIG. 1, after screen data of a 3D image signal is written from a first scan line to a last scan line (for example the 1080th line) in an order, a timing controller of the display does not write the data during a Vertical Blanking Interval (VBI) time, and at the moment the left-eye lens or the right-eye lens of the shutter glasses is enabled.
However, the screen data to be seen by the left-eye or the right-eye is written into a pixel unit of the display during the writing of the data. Since in fact, the backlight module continues acting during the writing of the data, and the shutter glasses are in a disabled state during the writing of the data, both the shutter glasses and the display do not present changes of the image into which the screen data is written. Therefore, the backlight module is in a useless power consumption state during most of the time, thus resulting in gratuitous waste of energy, increasing power consumption of an LCD panel, making a result of comparison between operating efficiency of the LCD panel, a life of a component, and actually consumed energy uneconomical, and increasing unnecessary power consumption cost.
Therefore, how to decrease power consumption of a display when the display presents a 3D image becomes a problem manufactures should contemplate.